The Study Of Long Gamma-ray Burst With Redshift Measured

Gamma ray bursts(GRBs)are the most violent radiation phenomena in the universe.They are the phenomena that gamma rays suddenly increase and then disappear in a short time.Since they were first discovered in the 1960s,they have been a hot research object in astrophysics.According to its duration,GRBs can be divided into long GRBs(LGRB,>2S)and short GRBs(SGRB,<2S).GRBs originate from cosmology.The study of the jet structure of GRBs and the comparison and analysis of the GRBs detected by the mainstream gamma ray burst detectors can help astronomers to further understand the relationship between GRBs and cosmology,the physical mechanism of its predecessor star system and central engine.In this paper,the history,characteristics and possible central engine physics mechar nism of GRB are introduced.In the second chapter,the hardware and software information of Swift and Fermi are introduced.In chapter three and chapter four,two works of LGRBs with red shift detection during Master period are introduced.The first work is the study of the structure model of GRB jet.By using Monte Carlo simulation,we study the effects of three kinds of models of LGRBs jet structure,namely Uniform distribution,Gaussian distribution and Power-Law distribution,on the isotropic energy and red shift distribution.We find that the mean total jet energy of LGRB is in the range of 49.79<logEc<52.71,which may be more than two orders of magnitude less than the isotropic energy derived directly from observation.Among the isotropic energy distributions of the GRBs obtained by the three models,only when θj=30°,the results show that the uniform distribution model is in good agreement with the observation(K-S test,P=0.0724).For the redshift distribution,the results of all models are similar,and they are not in good agreement with the observation(P<0.05).In conclusion,our results indicate that the current observational data may not be enough to distinguish the three jet models.In the second work,we compare the red shift,isotropic energy and peak luminosity distribution of LGRB samples detected by Swift and Fermi.Our preliminary results show that when the Swift sample adopts Power-Law spectrum,the energy and luminosity of the total sample are highly consistent with the Fermi total sample distribution calculated by band function,but for Swift LGRBs calculated through Band function by usingΓBAT-Epeak mpirical relationship,they consist not very well with Fermi.In addition,the common samples with Fermi of Swift in total sample is mainly concentrated in low redshift part.In the last chapter,I review and summarize the works I have done during my master’s degree,and look forward to the possible contributions to this field and subject in the future with the launch of new generation detecots of GRBs.The cosmological parameters through entire paper we adopt are:H0=71km s-1Mpc-1,ΩM=0.3,ΩΛ=0.7...